An infinite number of shapes and structures can be easily built with the 3 basic Goobi components: the Bar, the Ball and the Tripod. Goobi structures shape children's imaginations, induce their creativity and develop their sense of proportion. Parents love them because it teaches the children important lessons about problem solving, math and physics. The beginner pack comes 35 bars, 18 balls and 8 tripods for a total of 61 rainbow colored pieces. Marcia Pembroke, manager of Toadstool LLC in Hockessin, Del., said these sell well in her store, and two other retailers mentioned these as big sellers. See demo video from the WTHRA show